New Research Recap

Mounting Solutions

Chassis and Mounting

• Apart from bolts, latches/mounting quick release pins/aluminum extrusion rails are super good options for mounting mechanisms for sub systems

Mounting Carbon Fiber Tubes

• Shoulder bolts or pins can be used to mount frames to chassis

Carbon Fiber

Mounting Carbon Fiber Tubes

• Carbon fiber lugs are used as a joining piece between two carbon fiber pieces

  • an internal cylindrical piece is sanded down (same with internal tube) and you use adhesive to bond the two pieces together

  • Clamping tubes is an option, but probably a lot safer and stronger to use adhesive. Adhesive is likely air cured, but more research should be conducted to figure out what specific types of high-strength adhesives should be used

Working With Carbon Fiber

• Check out Carbon Fiber Q&A

• Weight savings may not be actualized due to complex mounting solutions

Drivetrain Design

• 4 wheel vs 6 wheel design still in discussion Flexible Drivetrain Design

• Lots of great research into the different types of suspensions used by other teams, but more discussion on what kind of objects we will need to traverse is required

• TBH all design options seem viable if done right, its more so just figuring out what our team wants to do

Wheels

• Research covered in Wheel Construction

• Offroad ATV's offer some great design inspo, where rear wheels have "sand paddles" for better driving, and smooth tires would be used on the front of the rover

Moving Previous Research

• previous research on 4 vs 6 wheel research was conducted

• research into beach tires were conducted, with some motor requirements

• previous research into carbon fiber was conducted as well to compare it to aluminum, with some fittings from McMaster spec'd out as well

Motor Integration Research

• Direct drive is great, as you don't need a power transmission system, although they require custom wheel hubs to use

• Chain drives are probably a better alternative to belt drives, as they require more maintenance but are easier to work with

• More motor research needs to be conducted 

Prototyping Plan

• Start with 3D printed prototypes for drivetrain configurations

• move to wood (constructed remotely) and figure out what exactly we want to learn from it

Main Configurations to Prototype (in order): MAY 4TH DESIGN DEADLINE

These are the designs we want to 3D print prototype and test

1. 6 wheel triple bogie suspension with rear rocker. Rear rocker allows for an additional degree of freedom on wheels which is useful for traversing over obstacles → Emily
   
   

   Open

   

2. Two bogie suspension + differential → Andrew
   
   

   Open

   

3. Rocker bogie suspension → Max

Quantifying Tests

1. Test chassis stability, potentially through placing a glass of water on chassis and seeing how much spills

2. We are also gonna test for clearance when traversing certain objects

3. Test likeliness to tip on different inclines

4. Standard wheels will be used to scale the design of systems to keep tests across different members consistent (1.25cm)

5. Further testing of designs with lego should be conducted after 3d printed tests, as 3D printed tests can be conducted right now

6. After we pick a design through testing, start simulations to optimize drivetrain design

To Research 

• Motor selection

  • Determine approximately the torque/speed requirements

  • Find some motor and gearbox candidates

• MATLAB learning, prepare basic simulations → Rehnuma, Asha, Elizabeth, Ali

  • Make a basic rocker bogie

  • Confluence page

Overall Constraints

• 6 wheels has been confirmed for drivetrain

• We still need to quantify height of chassis above ground, but its likely that drivetrain width and length will be on the cusp of 1.2m by 1.2m box

Defining More Constraints

• How are other components gonna be mounted on chassis? namely comms and ebox, or potentially science